223485777 nsn 2g 3g parameter setting

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Sharing Traffic 2G-3G • Load Base Handover 2G-3G • Cell Reselection 3G-2G 2G-3G • PUSH AMR

I insert classification level 1 © NSN Siemens Networks

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Load based Handover GSM -> WCDMA Load of GSM cell 100%

Load reason Handovers for speech

Speech Speechto toWCDMA WCDMA only with high only with highGSM GSMload load

More Morecapacity capacity for speech for speech

Packet PacketData Datato toWCDMA WCDMA regardless of GSM regardless of GSMload load

Higher Higherbit bitrates rates for data users for data users

80% Utran HoThScTpdc = 80%

Packet PacketBCCH BCCHparameters parameterscan canbe beused used totopush GPRS mobiles to WCDMA push GPRS mobiles to WCDMA

0% Soc Classification level 2 © NSN Siemens Networks

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Load & Coverage Reason Handover Load Loadreason reason Handover Handoverfor forspeech speech and for HSCSD and for HSCSD WCDMA low loaded

GSM high loaded

GSM GSM

GSM GSM WCDMA WCDMA

GSM GSM

GSM GSM WCDMA WCDMA

WCDMA WCDMA Load reason Handover

Soc Classification level 3 © NSN Siemens Networks

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WCDMA WCDMAcan canbe beused used to relieve GSM overload to relieve GSM overload GSM GSMcan canbe beused usedto toextend extend WCDMA WCDMAcoverage coveragearea area

GSM GSM

GSM GSM

Mobile moving

Coverage reason Handover


Load based Handover Process: GSM-> WCDMA Handover HandoverTriggering TriggeringThresholds Thresholdsset setininBSC BSC

Inter-RAT Inter-RATmeasurements measurementsstarts startsinincase case The RXLEV of the serving cell is above The RXLEV of the serving cell is aboveoror below belowthe thegiven giventhreshold thresholdQsearch_C Qsearch_C

Handover HandoverDecision Decisionisisdone doneinincase caseofof Load Loadofofthe theserving servingcell cell>>Load_Threshold Load_Threshold &&CPICH Ec/No> min Ec/No CPICH Ec/No> min Ec/NoThreshold Threshold

MS MSselects selectsthe thetarget targetUTRAN UTRANcell cellbased based on measurement results on measurement results Handover Handovercommand commandisissend sendtotoMSC MSC

Soc Classification level 4 Š NSN Siemens Networks

Presentation / Author / Date

Parameters are sent from the BSC to the mobile in the Measurement Information message MS is measuring the UTRAN cells continuously if they are defined as a neighbor , The number of GSM neighbor reported could be 3-6 depending on the set value of parameter FDD_MULTIRAT_REPORT (0,1,2=def,3).

The load is measured in the cell level by comparing the occupied TCHs to the available TCHs (20 s interval used) Load Threshold for Speech Calls or Transparent Data inter-RAT Handover: utranHoThScTpdc (Min Traffic Load TDHO), default = 80% minEcnoThreshold (Min CPICH EC/NO Threshold), default –15 dB


Hidden

Changeable

ISHO 2G -> 3G Parameters Parameter

Specification name

min traffic load for speech call

NSN parameter

Range

Default value

LOAD_THRESHOLD_FOR_S utranHoThScTpdc (LTSC) C_IS_HO

0-100%

80%

minimum CPICH Ec/Io level

MIN_ECNO_THRESHOLD

-24…0.5 dB

-15 dB

min interval between unsucc ISHO attempt

MIN_INTERVAL_BETWEEN_ minIntUnsuccIsHo (UMIU) UNSUCC_ISHO_ATTEMPT

0…255 s

3s

threshold for multi-RAT MS

Qsearch_C

0…15

15 (never)  rec. 7 (always)

minEcnoThreshold (MET)

qSearchC (QSRC)

Specification name

Parameter explanation

FDD_REP_QUANT

Indicates the reporting quantity for UTRAN FDD 0=RSCP, cells 1=EC/NO

Not tunable, Fixed value 1

3G_SEARCH_PRIO

Indicates if 3G cells may be searched when BSIC decoding is required

Not tunable, Fixed value 1

FDD_MULTIRAT_REPORTING

The number of cells from the access 0…3 technology/mode FDD that shall be included in the measurement report

Not tunable, Fixed value 2

Qsearch_C_Initial

Indicates the Qsearch value to be used in 0 = use Qsearch_I, connected mode before Qsearch_C is received 1 = ∞ (always)

Not tunable, Fixed value 0

Soc Classification level 5 © NSN Siemens Networks

Presentation / Author / Date

Value range

0 = no, 1 = yes

Note


Handover Control • GSM ISHO • Load Based Handover to WCDMA • Cell Reselection

Soc Classification level 6 © NSN Siemens Networks

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Cell Reselection 3G -> 2G CPICH EcNo

UE starts GSM measurements if CPICH Ec/No < qQualMin + sSearchRAT

SintraSearch

First ranking of all the cells based on CPICH RSCP (WCDMA) and RSSI (GSM)

SinterSearch

Rs = CPICH RSCP + Qhyst1 Rn= Rxlev(n) - Qoffset1

SsearchRAT qQualMin No

Serving WCDMA cell calculation, with hysteresis parameter

Neighbour WCDMA or GSM cell calculation with offset parameter

Yes

Rn (GSM) > Rs (WCDMA) And Rxlev (GSM) >QrxlevMin Second ranking only for WCDMA cells based on CPICH Ec/No Rs = CPICH Ec/No + Qhyst2 Rn=CPICH_Ec/No(n)-Qoffset2 Soc Classification level 7 © NSN Siemens Networks

Presentation / Author / Date

Cell re-selection to GSM Cell re-selection to WCDMA cell of highest R value


Cell Reselection 3G -> 2G UE ranks the serving cell and the measured neighboring cells to find out if reselection should be made  All the measured suitable cells (S-criteria) are included in the ranking.  Criteria for a suitable cell (S-criteria) is defined as  WCDMA intra-frequency neighbor cell:  CPICH Ec/No > AdjsQqualmin and CPICH RSCP > AdjsQrexlevmin

 WCDMA inter-frequency cell:  CPICH Ec/No > AdjiQqualmin and CPICH RSCP > AdjiQrexlevmin

 GSM cell:  Rxlev > Qrxlevmin

Ranking is done using Criteria R, and the UE reselects to the cell with highest Rcriteria. R-criteria is defined as:  For serving cell: Rs = Qmeas,s + Qhysts  For neighboring cell Rn = Qmeas,n – Qoffsetts,n  Qmeas is CPICH Ec/No for WCDMA cell and RxLev for GSM cell  GSM measurements can start when CPICH Ec/Io of serving cell is below Ssearch_RAT + QqualMin Soc Classification level 8 © NSN Siemens Networks

Presentation / Author / Date


Cell Reselection 2G -> 3G Cell Reselection

List

BCCH: FDD_Qm in, FD

Qsearch_I: 0..15; 1; 7 (always)

D_Qoffset

GSM MS starts WCDMA measurements if : RLA_C< F(Qsearch_I) for 0<Qsearch_I<=7 or RLA_C> F(Qsearch_I) for 7<Qsearch_I<=15

check

no priorities between WCDMA neighbors

at least every 5 s

Measurement Updates: • RLC_C value of the serving cell • + least 6 strongest non serving GSM cells

If, for suitable UMTS cell & for a period of 5 s: CPICH RSCP > RLA_C + FDD_Qoffset

and CPICH Ec/No ≥ FDD_Qmin

Fdd_Qoffset: select always (value is -infinity)

WCDMA cell reselection FDD_Qmin:

-20... –6; 2; -12 dB Soc Classification level 9 © NSN Siemens Networks

Presentation / Author / Date


Cell Re-selection Parameters • Qsearch_I and Qsearch_P define the threshold for non-GPRS/GPRS (respectively) capable

UEs to measure 3G neighbour cells when a running average of the received downlink signal level (RLA_C) of the serving cell is below (0-7) or above (8-15) the threshold Value

0

1

6

7

dBm

-98

-94

-74

If RLA_C < -94 UE starts 3G measurements

8

Always -78

9

10

14

15

-74

-70

-54

Never

If RLA_C > -70 UE starts 3G measurements

UE always measures 3G cells

• FDD_Qoffset and FDD_GPRS_Offset the non-GPRS/GPRS (respectively) capable UEs

add this offset to the RLA_C of the GSM cells. After that the UE compares the measured RSCP values of 3G cells with signal levels of the GSM cells Value

0

1

2

3

8

14

15

dBm

-always

-28

-24

-20

0

24

28

Always select irrespective of Soc Classification level value 10RSCP © NSN Siemens Networks

Presentation / Author / Date

Reselect in case RSCP > GSM RXLev (RLA_C) +28dB


Cell Re-selection Example: weaker WCDMA Non GPRS case RSCP/ RLA_C

Idle IdleMode Mode

Ec/No

Cell re-selection to WCDMA

RLA_C

Serving GSM Cell

Qsearch_I = -98 dBm FDD_Qoffset = -8 dB

Measurements starts (serving cell)

Neighbour WCDMA Cell

FDD_Qmin=0 -12 dB

RSCP Ec/N0 Minimum Quality Requirement for WCDMA 5 sec.

CPICH RSCP > RLA_C + FDD_Qoffset &

CPICH Ec/No ≥ FDD_Qmin Soc Classification level 11 © NSN Siemens Networks

Presentation / Author / Date

GSM GSM -> -> WCDMA WCDMA

t


Cell Re-selection Example: stronger WCDMA GPRS case RSCP/ RLA_C

Connected ConnectedMode Mode

Ec/No

RLA_P Cell re-selection to WCDMA

FDD_GPRS_Qoffset = 8 dB Qsearch_P = -98 dBm

Serving GSM Cell (Best)

RSCP Measurements starts (serving cell) FDD_Qmin = -20 dB Neighbour WCDMA Cell

Ec/N0

Minimum Quality Requirement for WCDMA t 5 sec.

Soc Classification level 12 © NSN Siemens Networks

Presentation / Author / Date

GSM GSM -> -> WCDMA WCDMA


How to avoid ping pong ? • When phone is camped on 3G, GSM measurements can start when CPICH Ec/Io of serving cell is below Ssearch_RAT + QqualMin. • When phone is camped on GSM, cell reselection to 3G is possible if CPICH Ec/Io of the candidate is above FDD_Qmin. • Therefore, to avoid ping pongs between 3G and GSM the following condition should be met: FDD_Qmin >= QqualMin+Ssearch_RAT CPICH Ec/Io

FDD_Qmin >= -12 dB

QqualMin +Ssearch_RAT Ssearch_RAT=4 dB

QqualMin=-18 dB

Camping on 3G

Camping on GSM Camping on 3G t

Soc Classification level 13 © NSN Siemens Networks

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PUSH AMR • Push Voice 3G-2G

Soc Classification level 14 © NSN Siemens Networks

Presentation / Author / Date


Forced Handover for AMR Voice Call AMR voice call setup in 3G • Feature can be used to push 3G AMR calls to 2G • Extreme parameter setting for ISHO trigger cause “UE Tx power” (event 6A)

WCDMA forced handover to GSM

GSMcauseTxPWRUL

GSM

FMCG; 0 (no) / 1 (yes)

FMCG: GSMcauseTxPwrUL FMCG: GsmUETxPwrThrAMR

UE

[..]

RNC RRC: RadioBearerSetup

RRC: RadioBearerSetupComplete RRC: MeasurementControl RRC: MeasurementReport (event 6A)

UE immediately answers with Measurement Report „push“ means Handover, not Directed-Retry ! Soc Classification level 15 © NSN Siemens Networks

Presentation / Author / Date

ISHO measurements & HO to GSM

Remember:

6A: UE Tx power > absolute threshold max. allowed UE Tx Power (e.g. 21 dBm) + GsmUETxPwrThrAMR: FMCG; -60..0; 1; -3 dB here: - 60 dB !


Forced Handover for AMR Voice Call • FMCG: GSMcauseTxPwrUL • Range and step: 0 (False), 1 (True) • Indicates whether a handover to GSM caused by high UE TX power level is enabled. The handover is enabled when the value of the parameter is "Used“ • To enable feature, setting must be 1 (True)

• FMCG: GsmUETxPwrThrAMR • Range and step: -60..0 dB • This parameter determines the UE TX power threshold for a CS voice connection. If the handover to GSM caused by high UE TX power level is enabled, the RNC starts inter-RAT (GSM) measurements when the UE TX power reaches this threshold. The UE TX power threshold is relative to the maximum TX power level an UE can use on the DPCH in the cell (or the maximum RF output power capability of the UE, whichever is lower • To enable feature, setting must be –60 dB

Soc Classification level 16 © NSN Siemens Networks

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THANKS

Soc Classification level 17 © NSN Siemens Networks

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